textproduct: Quad Cities

KEY MESSAGES

- Warming into Saturday with occasional chances for nuisance light showers in or near the local forecast area, but many more dry hours than those who experience a wetting rain.

- A clipper-like system late Monday night into Tuesday morning is forecasted to bring scattered (30-70%) showers and thunderstorms to the region.

SHORT TERM /THROUGH SATURDAY NIGHT/

Issued at 206 PM CDT Fri May 8 2026

Water vapor imagery(WV) and upper air analysis showing broad northwesterly steering flow wrapping around a large cut-off upper low acrs the Hudson/James bay region and down acrs much of the mid CONUS. Several embedded vort max's in this flow, with two of note for the local area...one being the wave currently rolling acrs southern IA and northern MO producing the showers acrs those areas, and another one further upstream still acrs southern Saskatchewan. As the wave in the south exits taking the shower activity with it through the evening, the upstream vort max or even multiple features will look to ripple in clipper-style down acrs the upper and mid MS RVR valley through Sat. Thus the local area will be open to passing patches or small clusters of mainly light showers into the weekend. But these features will have to battle an ongoing dry low to mid level airmass acrs the region for much precip to reach the sfc. One such lead vort max currently acrs central MN may try to induce some light spotty high based showers or sprinkles acrs the northeast half of the CWA tonight, with the above mentioned larger Saskatchewan wave producing showers acrs mainly MN into WI late tonight into early Sat afternoon. Some of this activity may try to bleed down to the Hwy 20 corridor on Saturday.

Overall though, the message should be that most of the area to have many more dry hours than impacted with showers through Saturday late afternoon. Low temps tonight in the mid 40s to low 50s being held up by south winds and some clouds, while high temps on Saturday helped out be pre-frontal WAA and deeper mixing/breezy wind regime helping boost temps well up in the 70s acrs most of the area. We may have a 10 degree range from the northern CWA to the south, depending on where layered cloud bands lay out.

Saturday night...Another vort max similar to the one occurring in our south right now, will look to propagate out of the central plains and produce sctrd showers and possibly a thunderstorm along and south of the Hwy 34 corridor Sat night. But the latest guidance still varies on how much precip will move acrs the local CWA and it may not be much if the latest ECMWF and CAM runs have their way.

LONG TERM /SUNDAY THROUGH THURSDAY/

Issued at 206 PM CDT Fri May 8 2026

Sunday...After whatever wave can ripple along and south of the area Saturday night, Sunday should be characterized by incoming ridging and cooling northerly boundry layer flow for a mainly sunny, dry but somewhat below normal temp day. Highs back in the 60s, and a cool Sunday night in the low 40s to upper 30s.

Monday...Highs look to continue to be near seasonable in the mid-60s to low 70s, but Monday night lows not as cool ahead of an incoming clipper system. Regarding that system, the pattern looks to shift Monday night as the winds trend southerly as the next low pressure clipper-like system closes in. Associated leeside WAA processes may produce a few late night showers or even a thunderstorm into at least the northwestern portion of the DVN CWA before 12z Tue.

Tuesday-Wednesday...The clipper system is forecast to dive into the Northern Plains Tuesday morning. Shortwave troughing and ridging will enhance divergence aloft over eastern Iowa, Wisconsin, and northern Illinois as a vorticity maximum pushes into Minnesota. The low-to-mid-level response will also be strong with a 850-700 mb f- gen band developing over the CWA, WAA at 850 mb ahead of the front, and a deepening low pressure over northern Iowa. The only limiting factor is the lack of mid-level moisture with model disagreement on the exact placement of a narrow band of high 700 mb RH. LREF currently has a 70% spread on 700 mb RH values Tuesday morning, but there is agreement on a band of heavier precipitation (0.2 to 0.4 inches) moving across northwest Illinois, but the southwestward extent remains questionable.

As the low pressure continues to slide to the southeast into the Ohio River Valley Tuesday night, a weak surface trough underneath the passing 500 mb trough axis could support some rain showers through Wednesday morning before another high pressure anchors over the Northern Plains as longwave ridging builds over the Rockies.

Thursday...A little deju vu from Monday night as the surface high pressure over the Upper Mississippi River Valley shifts to the east, setting up southeasterly flow over Iowa ahead of the next approaching cold front. There is the potential for some pre-frontal showers, but there is model uncertainty on the position of the developing warm front with a 10-degree spread in high temperatures according to the LREF.

AVIATION /18Z TAFS THROUGH 18Z SATURDAY/

Issued at 1240 PM CDT Fri May 8 2026

Generally another VFR TAF fcst through midday Saturday. Bouts of mid and high clouds streaming acrs the area with dry LLVL's, and will bank on the ongoing showers staying south of the BRL site this afternoon. Another upper wave dropping down acrs MN and WI may allow for a few light showers and sprinkles to skirt acrs the northeast half of the local fcst area tonight, but again ongoing dry low to mid level airmass may keep most of that precip in virga form and will not mention any precip in the TAFs. Light southerly sfc winds will veer to the west and increase to 8-12 KTs through this evening with a sfc trof passage, but then back again to the south overnight. Another stronger front will veer the winds again to the west-northwest by midday Saturday and they may gust over 20 KTs into Sat afternoon.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.